Tobacco-feeding apparatus



Feb. 28, 1956 D. ;w. MoLlNs 2,736,319

TOBACCO-FEEDING APPARATUS Filed June 18, 1954 ATTORNE YS United StatesPatent O 'roBAcco-FEEDnsG APPARATUS Desmond Walter Molins, Deptford,London, England, as-

signor to Molins Machine Company Limited, London, England, a Britishcompany This invention concerns improvements in or relating totobacco-feeding apparatus, e. g. for cigarette-making machines of thecontinuous rod type.

In such feeding mechanisms cut tobacco is placed in a hopper and is fedtherefrom on to an endless band or in some cases on to a web ofcigarette-paper. Usually the tobacco so fed is picked by -afast-rotating picker roller, and in some cases the tobacco after leavingthe picker is winnowed, that is, it is engaged by moving vanes andthrown upwardly and forwardly thereby to enable heavier particles, suchas pieces of stalk, to be separated from the lighter tobacco so thatthey can be excluded from the tobacco from which the cigarettes are tobe made. This is usually done by arranging a wall or chute in such aposition that as tobacco is thrown upwardly and forwardly, the heavierparticles, which owing to their greater mass travel further, are carriedover the wall, while the lighter particles fall short of the upper edgeof the wall. Usually a compartment is provided behind the wall toreceive the heavier particles.

The pieces of tobacco stalk which sometimes occur in cut tobacco are notonly heavier than the shreds of tobacco leaf, but also harder. It is anobject of the present invention to make use of these characteristics inproviding improved apparatus for separating pieces of stalk from thetobacco shreds which it is desired to incorporate in cigarettes.

According to the present invention there is provided tobacco-feedingapparatus comprising a smooth and relatively hard travelling conveyorsurface, and means to cause showered cut tobacco to strike said surfaceat an anglesuch that hard particles of tobacco, such as pieces of stalk,tend to bounce and slip rearwardly over said surface so as to fallrearwardly from the latter,'while softer particles tend to remain onsaid surface so as to be carried forwardly by it.

The said means may comprise a winnowing device arranged to throw cuttobacco upwardly and in a direction such `as to cause the tobacco tofall towards said surface while having a component of movement in theopposite direction to that in which the surface is moving, whereby hardparticles such as stalks, which owing to their greater mass, travelfurther than lighter particles, tend to strike the rear part of the saidsurface, while lighter particles tend to strike theforward part of saidsurface., V

v The saidr surface may be so 'located as to discharge tobacco carriedthereon on to a moving conveyor in the trough of a cigarette-makingmachine.

The said surface may be the upper surfacevof an endless conveyor bandcomprising polyvinyl chloride.

The said surface may be caused to be moved in timed relationship withthe said moving conveyor in the trough and stop when said movingconveyor stops, whereby tobacco moving so as to fall on said surface atthe moment when the said moving conveyor stops is prevented from fallingon the latter.

A wall may be located above said surface to assist 2,736,319 ce PatentedFeb. 28, 1956 in segregating heavier from lighter tobacco particlesfalling towards said surface, the Wall being spaced apart from thesurface to permit tobacco which falls on the surface to the rear of thewall to be carried forwardly by said surface.

Apparatus according to the invention will now be described by way ofexample with reference to the accompanying drawing, which shows asection through tobaccofeeding apparatus in a cigarette-making machine.

Tobacco is fed from a hopper into the teeth of a carded roller 1 onwhich it is formed into an even layer, or carpet, as it is sometimescalled. The tobacco is picked from the teeth of the roller 1 by afast-rotating picker roller 2 which throws the tobacco against arotating winnowing element having vanes 3. A guide 4 guides the tobaccofrom the roller 2 to the winnower. The vanes 3 of the winnower, whichrotate in the direction shown by the arrow, throw the tobacco upwardlyand forwardly.

An endless conveyor band 5 is arranged to pass over three rollers 6, 7and 8 which are rotated so as to move the band in the directionindicated by the arrow. The band 5 is made of the plastic materialknown-'as polyvinyl chloride, and has a smooth and somewhat hardsurface. The part of the band from the roller 6 to the roller 7 isarranged at `an angle of 25 to the horizontal, sloping upwardly in itsdirection of movement. The part of the band extending between the roller7 and the roller 8 slopes downwardly. A vertical wall 9 is located abovethe band 5, with its lower edge clear of the bandas shown.

Between the endless band 5 yand the winnower a pair of converging guidewalls or chutes 10 and 11'are arranged to extend downwardlytowards atobacco trough 12 along which runs a tobacco tape 13;

The roller 8 is arranged to be rotated by means of a chain 14 passingover a sprocket 15 on the shaft 16 of the roller 8, and a sprocket 17 ona shaft 18 which is arranged to rotate in the direction shown by thearrow. The shaft 8 may be the main drive shaft of the machine, or may bedriven in any convenient and suitable way in synchronism with the otherparts of the machine, so that the band 5 can be moved ,in timedrelationship with Vthe carded roller 1, the picker roller 2, andwinnower 3, andv other parts of the machine including the drive for thetape 13.

The shaft 19 of the roller 6 is journalled in bearings 20 which aremovable along a slide 21 for the purpose of adjusting the tightness ofthe band 5'. An adjusting screw 22 is provided for this purpose.

A brush 23 is mounted beneath 'the lower run of the band 5 and arrangedto engage the band in clean it.

Tobacco thrown upwardly and forwardly by the vanes 3 of the winnowerfalls on the upper surface of the band order to 5. The heavier particlesof tobacco, which in general consist of pieces of tobacco stalk, tend totravel further than the lighter particles, due to their greater mass,andA therefore tend to pass over the wall 9 and to fall on the portionof the band between the rollers 6 and 7. The lighter particles, whichare chiey shreds of tobacco leaf, mainly tend to fall short of the wallV9, or to strike it, and thus to fall on ,the part of the band betweenthe rollers 7 and 8. Some of these lighter particles, however, travelfurther than others, possibly in some cases being carried by heavierpieces of stalk, and it is found that not only pieces of stalk but alsoshreds of tobacco leaf, suitable for incorporating in cigarettes, passover the wall 9 and fall on the upwardly sloping part of the bandbetween the rollers 6 and 7. In the known arrangement where a wall suchas the wall 9 is relied upon to separate light from heavy particles,these shreds which were thus carried over the wall together with piecesof stalk would be segregated from the shreds which fell araasw 3 shortofthe wall, and would thus be excluded from the tobacco used. in makingcigarettes.

It is found, however, that in the arrangement described and illustrated,when particles which include pieces of stalk and also shreds of tobaccoleaf are thrown by the winnower varies 3 over the wall 9 so as to fallon to lthe band 5, pieces` of stalkv which strike the upwardly slopinglength of the hand between the rollers 6 and 7 tend to bounce and slipon the relatively hard, smooth surface of the band, and to fall off theband to the left of the roller 6 as viewed in the drawing, while shredsof tobacco leaf which fall on the same part of the band tend to remainon it and to be carried forwardly and upwardly by the band, passingvbeneath the wall 9. Lighter particles which fall directly on theVportion of the band between the rollers 7 and' 8 or which strike theface of the wall and drop down on to that portion of the band are, ofcourse, also carried forwardly by the band.`

It is believed that this behaviour of the pieces of stalk is due totheir relative hardness, and. to the relative hardness and smoothness ofthe surface of the band 5, as well as to the angle at which they strikethe band, which de pends partly on the angle at which they are thrown bythe winnower and partly on the angle to the horizontal at which theupwardly sloping part of the band is arranged between the rollers 6 and7. As stated above, in example illustrated this angle is 25, which isfound suitable for the purpose in this particular construction. In otherconstructions, for example, where the winnower is so arranged as tothrow the tobacco at a different angle, it may be necessary to alter theangle at which the band is arranged to the horizontal. Also the positionand height of the wall 9 may have to be adjusted to get the best resultsin any particular construction. In addition the position and arrangementof the band relative to the trough 12 and to the picker roller 2 andwinnower 3 may require adjustment to obtain the best results in anyparticular construction.

The material used for the band 5, namely polyvinyl chloride, is found tohave a sufciently hard, smooth surface for the present purpose but ifother materials are used itis necessary to choose a material whosesurface is hard and smooth enough to cause the pieces of stalk to bounceand slip on it, and' here again it may be necessary to arrange the bandat a different angle from that chosen in the present example, namely tothe horizontal. However, it would seern that in a construction madeaccording to the drawing and having a band having a smooth surface ofpolyvinyl chloride only a very slight deviation of say 2 or 3 each wayfrom 25 will y provide the desired result whereby the stalks will falloff the band whilst the softer acceptable tobacco particles will clingto and remain on the sloping surface.

The tobacco carried forwardly by the band 5 is discharged into thetrough 12 and falls on to the tobacco tape 13, which carries itforwardly in the form of a stream. The particles, principally pieces ofstalk, which fall from the band to the left of the roller 6 can becollected in a suitable receptacle or disposed of in any suitable andconvenient way.

The use of the band 5 to intercept falling tobacco which has been thrownby the winnower has another advantage in addition to that alreadydescribed.

In constructions previously proposed for winnowing tobacco, where thetobacco is thrown towards a wall `arranged to intercept the lighterparticles, while heavier particles are segregated. solely by passingover thev upper edge of the wall, the particles intercepted by the wallfall downwardly directly into the trough of the cigarettemaking machine.Thus at any given instant during operation there is a quantity oftobacco which has left the winnower but has not yet reached the tobaccotape in the trough. In this earlier arrangement, if the machine isstopped, the equivalents of the roller 1, the picker 2, the winnower 3and the tape 13 arc normally all stopped at the same time. All thetobacco which has left the winnower, however, must fall on the tobaccotape which is now stationary, and thus an excess of tobacco accumulateson the tobacco tape whenever the machine is stopped. This may and oftendoes cause choking when the machine is restarted.

Where however the whole or the greater part of the tobacco thrown by thewinnower is intercepted by the band 5, as in the present construction,only a relatively small quantity of tobacco, namely that which hasalready started to fall from the band 5, falls on to the tobacco tape 13after the machine has stopped, because the band 5 can by the arrangementdescribed above for driving the roller S in synchronism with the otherparts of the machine, be arranged to stop simultaneously with theseother parts. This will result in an excess of tobacco on the band 5, butthis is more easily dealt with than an excess in the trough.

What I claim as my invention and desire to secure by Letters Patent is:

1. Tobacco feeding apparatus comprising a toothed conveyor for cuttobacco, means to pick tobacco from said conveyor, a winnowing devicearranged to receive tobacco so picked and throw it upwardly andforwardly, a partition located to intercept some of the tobacco sothrown while permitting heavier particles to pass over it, and a secondconveyor having a smooth, relatively hard surface disposed transverselyof and extending beneath said partition, said second conveyor moving ina direction opposed to the forward direction of movement of the throwntobacco, the rear part of said second conveyor being located in aposition to intercept only tobacco particles thrown over said partition,whereby hard particles such as stalk are thrown so as to strike the saidrear part and tend to rebound therefrom in a direction opposed to thedirection of movement of said second conveyor, while softer particlesstriking said second conveyor surface tend to remain on it and to becarried forwardly by it.

2. Apparatus as claimed in claim 1 wherein the said rear part of thesecond conveyor slopes upwardly toward the said partition.

References Cited in the file of this patent UNITED STATES PATENTS1,318,003 Wheeler Oct. 7, 1919 1,321,201 Young Nov. 11, 1919 1,903,931Molins Apr. 18, 1933 1,907,575 Podmore May 9, 1933 2,515,778 KnowlandJuly 18, 1950 FOREIGN PATENTS 599,877 Great Britain Mar. 23, 1948650,076 Great Britain Feb. 14, 1951

